- There are two players in the game (X and O)
- Players take turns until the game is over
- A player can claim a field if it is not already taken
- A turn ends when a player claims a field
- A player wins if they claim all the fields in a row, column or diagonal
- A game is over if a player wins
- A game is over when all fields are taken
As a player
So that I can play the game
I want to be able to claim a field on the grid
As a player
So that I can play against an opponent
I want to takes turns claiming a field
As a player
So that I can win the game
I don't want my opponent to be able to claim one of my fields
As a player
So that the game can be won
I want the game to finish if a player claims three fields in a row
As a player
So that I can play again if I can't claim a field
I want the game to be over if all fields are taken